The plants are one week old! They seem to be doing really well, for the most part. As expected, as the concentration of D2O increases the plants develop slower. Also as expected the plants also exhibit leaf decolorization. Notice how in 60, and 70% D2O the leaves are a pale green. In 80% the plants are too small to notice growth. It also seems that the plant in 5% D2O is growing the fastest, which seems to be in line with my observations from the last trial run, and also with hypotheses from my dissertation (to be posted as soon as it is all finished). I will have to record some observations of the plants in DDW and compare them to 5% D2O and 10% D2O.

Normally, I use a pipetter that one would use for small volumes to deposit the seeds, but because the tubes are so much bigger than the ones in the past I need to alter my method. Today I used a glass Pasteur pipet with a very nice long tip. I used the wrong kind of bulb, so it was more challenging than expected, but worked well enough.

Also because my test tubes are much bigger than before, I made the mistake of not purchasing a test tube holder. So I had to fashion one from spare lab components. Check out my system:

Test tube holder for 25mm diameter tubes.

It’s made from the breadboard that has become my plant station, screws, and nuts. Pretty simple, and works amazingly well.

Well there is my idea of how to present my dissertation. I’m not sure if/where I should put my discussion on open notebook science. Also there are a couple things that I could see going elsewhere. I could describe the yeast and e. coli stuff in parallel instead of one after another. Also the HD exchange stuff could easily go right after the yeast, e. coli, or even the tobacco seed stuff. What to do…

Otherwise I think the story is pretty compelling: history of D2O and the unanswered question by Lewis. Investigations into D2O effects and trying to understand low D2O concentration effects, effects on macromolecules, and the understanding of large volume/long-term HD exchange.

Any feedback you may have would be GREATLY appreciated. I’ll send you a figshare t-shirt, or if you are XL, I’ll send you a hoodie (but I only have one).

Like this:

I got some awesome new data to show. The first is the compilation of all the Repeating Crumley experiments. And the second is some new data that I’ve been meaning to create and now have with the help of Koch.

Tobacco seed germination rates

The data above is the compilation of all the RC data. Each trial had different water types, but I combined the samples that were the same in every set (DDW, DI water, 33% D2O, 66% D2O, and 99% D2O). Steve adapted his R-code that applies binomial confidence intervals to a data set and used it on this data. If that makes no sense, then just know that the dotted lines are the most probable range of germination rates. For instance, in 66% D2O there is a ~70% likelihood that seeds will germinate at a rate within the dotted yellow lines.

Now it’s time for some brand new data:

tobacco seed root length

Here we went through the pictures from Trial 5 and compared the growth rates of the roots. We calculated the lengths of various seeds in each image and tracked the changes from image to image. We chose DI, DDW, and 1% D2O, because the D2O concentrations are relatively similar and because we wanted to test a hypothesis from a while ago. It’s interesting that the seeds in DDW and D2O grow at the same rate, while seeds in DI water grow at roughly half the speed.